Currently, closing systems with the capability of dispensing are widely used for beverage containers of various types, in particular for water, tea, fruit juices and sports drinks, mainly of the disposable type which are generally disposed of once the container is emptied. Normally, such closing systems comprise a valve device which, once made accessible by the removal of a dedicated protective cover, can be opened manually, for example by applying a certain traction, and then brought to the mouth for dispensing the beverage. This type of closure is especially used by sportsmen, for example by cyclists, but not only, who in this way can quench themselves even while in special positions without danger of spillage of the beverage and also using only one hand, with the aid of a grip by their lips or teeth. Today, a cap is particularly widespread for such bottles for sports use having an opening quite simple to be operated by the user, as shown in FIG. 7, which consists of a valve with a cylindrical outer surface, slidably inserted around a guiding and supporting element, which is forced open by axially sliding it with the hands or the teeth in a direction distal to the bottle body. Closing occurs by axially pushing, again with the hands or the teeth, the valve towards the bottle body. Since the closing valve is normally placed in contact with the user's mouth, a cover is provided, which is disposable or insertable again for the protection of the valve from external contaminants. This type of cap also has drawbacks of hygienic nature. The valve is operated both in closing and opening by the mouth and/or the hands, thereby excluding the use of the same container by other users who do not accept a mouth contact with caps already placed in the mouth or touched with the hands by other people. Moreover, one of the problems associated with such a type of cap is related to the practical almost impossibility to use it on bottles containing carbonated beverages which, at the time of opening, if no adequate precautions are taken, can project either gas or the beverage itself with force, possibly in the user's mouth or on his face. Last but not least, a problem with this type of cap is the weight of the complete cap which is large enough due to the fact that the stiffness of the opening valve must be ensured by a suitable thickness of plastic material, the valve being normally grasped with the teeth, which may deform it, preventing proper closing back.
The need of providing a cap of the sports type which allows the above drawbacks to be overcome is therefore felt.